Power transistors are semiconductor devices employed for switching power on and off. Different power transistor configurations are available, including insulated-gate bipolar transistors (IGBTs). The IGBT design combines the output switching and conduction characteristics of a bipolar transistor with the voltage-control of a MOSFET. IGBTs are often employed in, but are not limited to, scenarios involving low duty cycle, low frequency (e.g., below 20 kHz), high-voltage (e.g., above 1000 Volts), high temperature (e.g., above 100° Celsius), and/or high output power (e.g., above 5 kW).
Some of the issues that negatively impact IGBTs include switching losses and performance degradation over time due to thermal cycling. Recent efforts to improve IGBT characteristics include the introduction of a buried junction (sometimes called “floating” junction or “super” junction) into the drift region. Efforts to improve buried junction design and/or manufacturing techniques are ongoing. Buried junction architectures and improvements thereof are applicable to IGBTs as well as other semiconductor devices.